CVE-2023-29400: stdlib - Improper Handling of Empty HTML Attributes

golang-1.15 Updated 02 Oct 2025

Summary

11/05/2023

Disclosed on

N/A

Severity

No i

Fix available

High

Severity

7.3

CVSS Score

CVE-2023-29400: Templates containing actions in unquoted HTML attributes (e.g. Affects golang-1.15 versions < 484330d038d060c6e4db3dc8e6ea2b811b2a44d8. No fix is published. How to fix ↓

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Background

The stdlib package is a part of the Go programming language and provides a collection of standard libraries for various functionalities. It includes modules for file I/O, networking, cryptography, and more. The package is widely used in Go applications and forms the foundation of many projects. However, a vulnerability has been discovered in the package's html/template module, which can lead to improper handling of empty HTML attributes.

Vulnerability Detail

The vulnerability in the stdlib package's html/template module arises from the improper handling of actions in unquoted HTML attributes when executed with empty input. This can result in unexpected output when the templates are parsed due to HTML normalization rules. Attackers can exploit this vulnerability to inject arbitrary attributes into HTML tags, potentially leading to cross-site scripting (XSS) attacks or other security breaches. The vulnerability has a CVSS score of 7.3, indicating a high severity level.

How To Fix

No fixed version is published for this vulnerability.

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Workaround

There is no specific workaround mentioned for this vulnerability. However, developers can mitigate the risk by carefully reviewing and validating user input before using it in templates. It is essential to sanitize and escape any user-generated content to prevent potential injection attacks. Implementing a robust input validation mechanism can help minimize the impact of this vulnerability.

Conclusion

The stdlib package's html/template module is vulnerable to improper handling of empty HTML attributes, which can lead to injection of arbitrary attributes into HTML tags. This can result in cross-site scripting (XSS) attacks or other security breaches. It is crucial for developers to update the stdlib package to the fixed versions and review and update any affected templates. For further support on vulnerability remediation, please contact DevNack.com.

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